COURTSHIP 265 
and too frequent yielding to sexual impulse.* He thinks it 
probable that “in order to preserve the species the discharge of 
the sexual function must be rendered difficult, since the impulse 
to it isso powerful that, without some such arrest, it might 
easily become prejudicial to that end. This same strength of 
impulse is,” he adds,f “itself necessary to the preservation of 
the species ; but, on the other hand, dams must be opposed to 
the impetuous stream, lest the impulse expend itself before it is 
made effectual, or the mothers of the race be robbed of their 
strength, to the detriment of their offspring.” It has its 
origin in the general fact that, before any important motor 
discharge takes place, there is apt to be a preparatory and 
gradually increasing excitement. But this is specially empha- 
sized in association with the sexual impulse. As Professor 
Zeigler wrote, in a private communication to Dr. Groos,t 
“ Among all animals a highly excited condition of the nervous 
system is necessary for the act of pairing, and consequently we 
find an exciting playful prelude very generally indulged in.” 
Courtship may thus be regarded from the physiological 
point of view as a means of producing the requisite amount of 
pairing-hunger ; of stimulating the whole system and facilitating 
general and special vascular changes ; of creating that state of 
profound and explosive instability which has for its psycho- 
logical concomitant or antecedent an imperious and irresistible 
craving. This not only overcomes the coyness of the female, 
but generates and strengthens the ardour of the male—a point 
on which, perhaps, Professor Groos does not lay sufficient 
stress. For the process is reciprocal ; and though the male 
leads in the ardour of courtship, yet this ardour constantly 
grows till at last it overcomes the barriers of reluctance. 
Courtship is thus the strong and steady bending of the bow 
that the arrow may find its mark in a biological end of the 
utmost importance in the survival of a healthy and vigorous 
race. 
The coyness and reluctance of the female afford the 
* Op. cit. p. 283. t+ Op. cit., p. 248. 
t Op. cit., p. 242. 
